Unfortunately for Donald Trump, the front-runner heading into a contested Republican convention has never won the White House and most of the time does not even secure the party’s nomination. (Associated Press) more >

If Donald Trump finds himself in a contested convention this summer, a looming question for the Republican presidential front-runner will be whether he is a Lincoln or a Dewey.

Mr. Trump obviously would prefer to follow in the footsteps of Abraham Lincoln, who emerged the nominee from a brokered Republican convention in 1860 and went on to win the White House and become one of America’s most revered presidents.

Unfortunately for Mr. Trump, the experience of Thomas E. Dewey at contested Republican conventions is more common and far less inspirational. The front-runner heading into a contested Republican convention has never won the White House and most of the time does not even secure the party’s nomination.

The trend may be weighing heavily on Mr. Trump, who insists that the convention will have to pick him if he has more delegates than any other hopeful but short of the 1,237 majority needed to win on the first ballot.

“The notion that you go in with a plurality, therefore you deserve the nomination is just flat wrong,” said Merrill Matthews, resident scholar at the Dallas-based think tank Institute for Policy Innovation.

“It would not surprise me if we go to a contested convention and Trump ends up losing in that contested convention,” he said. “But I think it is too early to say. We have to see if the voters begin to gravitate toward him, as they typically do in presidential elections, and even if he doesn’t get 1,237, if the momentum is clearly behind him, I think it would be hard to deny him the nomination.”

Still, Mr. Matthews stressed that Mr. Trump will have to close the deal on the convention floor.

“He’s got to make the case to the delegates there,” he said. “He needs to persuade the other delegates that they should change their vote to him.”

Dewey ended up like most candidates who enter the Republican convention with the most delegates but short a majority — a position Mr. Trump could easily find himself in July in Cleveland — either passed over for the nomination or the loser in the general election.

Dewey experienced both outcomes. He was denied the nomination in 1940 and received it in 1948 only to lose that November to Democrat Harry S. Truman, despite the famously erroneous banner headline on the front page of The Chicago Daily Tribune.

In 1940 and eight years later, Dewey had a plurality of delegates when the convention opened.

In the history of the Republican Party, there have been 10 conventions where no candidate arrived with a majority of the delegates needed to clinch the nomination on the first ballot.

At seven of those brokered conventions, the candidate who arrived with the most delegates did not win the nomination. Half the time, the nomination went to the candidate who had the fewest delegates.

Lincoln was one of the candidates with the fewest delegates at the start of the convention. Another was Rep. James A. Garfield of Ohio, who entered the Chicago convention with no delegates but got the nomination after 36 ballots, the longest convention vote in Republican history.

In all three cases, when the candidates with the most delegates at the start of a contested convention emerged as the nominee, that candidate lost in the general election. Dewey shares that dubious distinction with Supreme Court Justice Charles Evans Hughes and U.S. Sen. James G. Blaine of Maine.

Hughes lost a hard-fought and acrimonious race against incumbent President Woodrow Wilson in 1916. Blaine was beaten in the 1884 election by New York Gov. Grover Cleveland, which was the first win for Democrats in six contests and broke the longest losing streak for any major party in U.S. history.

However, Mr. Trump can take solace in the fact that all the contested conventions in Republican history occurred before the modern primary and caucus system, which was established after 1968.

“As Harry Truman once put it, primaries were ‘eyewash’ — they didn’t matter much. Party leaders chose nominees before or during conventions,” said Larry Sabato, director of the University of Virginia’s Center for Politics.

He said the closest recent history has come to a brokered Republican convention was 1976 in Kansas City, which was not technically “contested,” although incumbent President Ford faced a strong challenge on the floor by former California Gov. Ronald Reagan.

“Ford was narrowly ahead of Reagan, but his nomination was certainly not a foregone conclusion,” said Mr. Sabato, who attended the convention. “Now, with only two candidates, it would have been difficult to force a second ballot, unlike 2016. Yet the two camps had pitched battles and tried out new stratagems almost hourly.”

He wondered whether one of the remaining Republican candidates will use Reagan’s ploy of naming a running mate in advance, “in order to shake loose the delegates needed either to be nominated on the first ballot or to force the convention to a second ballot.”

He suggested that “wild speculation” about running mates could commence.